As of this 11.30 am today, (Wednesday 6 June 2012), there were 33 confirmed cases of Legionnaire’s disease in Edinburgh, mostly in the south-west of the city.
One man in his 50’s died yesterday in the city’s Royal Infirmary, and several more are in intensive care.
The disease has an incubation period of up to 14 days, and the number of cases is expected to rise until this weekend. Edinburgh’s public health specialists have refused to rule out further deaths. The Scottish government is convening an emergency meeting later today to consider what other measures can be taken on top of those already in place.
It is important to note that Legionnaire’s disease is not contagious. It is a severe pneumonia-like illness resulting from exposure to Legionella bacteria. As is already clear, it is a potentially fatal form of pneumonia and all groups are susceptible to infection. However, some groups of people are at a higher risk, including:
- children under the age of five
- those over 45 years of age
- smokers and heavy drinkers
- people suffering from chronic respiratory or kidney disease
- anyone with an impaired immune system
Legionella bacteria are widespread in natural water systems, for example in rivers and ponds. However, the conditions are rarely right for people to catch the disease from these sources. Outbreaks of the illness generally result from exposure to Legionella growing in purpose-built systems where water is maintained at a temperature high enough to encourage growth.
Examples of these include cooling towers, evaporative condensers, spa pools, and hot water systems used in all sorts of premises (work and domestic) including shower systems. A water system includes all plant/equipment involved and components associated with that system, e.g. all associated pipe-work, pumps, feed tanks, valves, heat exchangers, quench tanks, chillers etc. It is important that the system is considered as a whole and not, for example, the cooling tower in isolation.
People can catch Legionnaires’ disease by inhaling small droplets of water, suspended in the air, containing the bacteria. Certain conditions increase the risk from Legionella, including:
- water temperature between 20–45 °C, which is suitable for growth
- creating and spreading breathable droplets of water, e.g. aerosol created by a cooling tower, or water outlets stored and/or re-circulated water such as air conditioning units and shower systems
- a source of nutrients for the organism e.g. presence of sludge, scale or fouling
- The symptoms of Legionnaires disease are similar to those of flu, i.e. high temperature, fever and chills, cough, muscle pains and headache. In a severe case, there may also be pneumonia, and occasionally diarrhoea, as well as signs of mental confusion. Once the bacteria infect the lungs, carriers may also experience a persistent cough, later including mucus or blood, shortness of breath and chest pains.
Legionnaires’ disease does not spread from person to person and cannot be contracted by drinking contaminated water.
In light of this outbreak in Edinburgh we strongly recommend all employers with systems that can create a mist or spray of water to ensure they have an up-to-date, suitable and sufficient risk assessment.
Law At Work would be delighted to assist any businesses who need help in this areas. For further details please contact Ian McKinnon, LAW’s Head of Health and Safety Services.